Consider sourcing a diff pinion seal for when it's needed. I wouldn't recommend changing it until it leaks but finding it twenty years could be a challenge unless it's on your shelf.

Good luck!!!

Just got a quote from the Mercedes Benz dealer. Every single part is still available new, which is simply incredible.

What's more, not a single part can be considered expensive except for one - the drive shaft centre support at $200. I'm going to get the OE part regardless.

On those items in particular that is a good call to go OE. Remember to mark the orientation between the two halves first...before doing anything.

Good luck!!!

There is a dust boot that goes over the splines of the two halves of the driveshaft that should be replaced while it is apart.

Good luck!!!

This one?

https://www.pelicanparts.com/More_Info/2024110497MBZ.htm?pn=202-411-04-97-MBZ&bt=Y&fs=0&SVSVSI=3305

Yes, that is the one. Not sure what the difference is but there is a special grease for splines. Motorcraft makes one, it is blue. Thoroughly cleaning and lubing the splines with any quality grease should be fine.

Good luck!!!